


Study 394

by thursdayshunter



Category: Supernatural
Genre: Amnesia, Bestiality, Body Modification, Bottom Dean, Breeding stand, Cock Cages, Dean/OMCs - Freeform, Dehumanization, Drugged Sex, Gags, Humiliation, Knotting, M/M, Medical Examination, Medical Procedures, Medication, Multi, Name Calling, Orgasm Denial, Other, Public Sex, Public humilation, Verbal Humiliation, Voyeurism, unable to orgasm, very dubcon
Language: English
Status: Completed
Published: 2017-02-20
Updated: 2017-02-20
Packaged: 2018-09-25 18:09:16
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 8,133
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9836987
Author URL: https://archiveofourown.org/users/thursdayshunter/pseuds/thursdayshunter
Summary: It was good money. It was really good money and they were in desperate need of money. People did studies all the time, received the money and went about their way. Even the medical studies.Written for a prompt.





	

**Author's Note:**

> PLEASE READ THE TAGS BEFORE CONTINUING! Seriously you have been warned. This was written for a prompt.
> 
> ALSO studies are NOT like this at all. Seriously. This is nowhere near what happens in an actual study of any kind (unless there is something I haven't heard of) so PLEASE don't take this as a good representation of what happens in a study, what is allowed or anything about rights/medical equipment/drug studies/etc.

It was good money. It was _really_ good money and they were in desperate need of money. People did studies all the time, received the money and went about their way. Even the medical studies.

The whole process was easy, far easier than the more illegal means they had used in the past and Dean had seen the dollar amount offered. They had more than enough money for Sam to get by on his own for the three weeks the study required and Dean’s food as well as boarding expenses were covered free of charge during the study.

They were desperate for any kind of money and this study would give them more than enough for a few months. He wasn’t sure what kind of study offered this kind of cash but Dean would rather offer himself as a participant than risk Sam.

If it worked out and he got through it without problems Sam could always use one of their fake IDs to join up so the researchers wouldn’t know they were related.

This was a literal win-win situation and they would come out of it with far more money than they currently had.

Dean had left the car with Sam, reluctantly, and took a taxi to the research facility with his bag of essentials. At least he wouldn’t really have to worry about anything for three weeks.

He glanced around as he walked up to the desk, everything was clean and bright, flashing a smile and turning on the charm.

“I’m here for the study in your ad.”

Grey eyes widened briefly before a smile curled painted lips and Dean grinned back in response. “Study 394?”

Mentally Dean cursed, _Fuck. Is that the right one?_ , but outwardly nothing showed. “Yeah. Sounds about right.”

“Excellent!” she turned, pressed a button, “Tell Jackson we have a subject for 394. We’ll need the contract ready for the participant.” Dean ignored the response as he glanced around at the desk he was leaning on until she turned back to him, “Just sign in here and fill out this form. Make sure you’re completely honest. Everything is confidential and your participation will only be kept together with your assigned number.”

Dean signed his name with a flourish, “Do you need ID or anything?” he hoped not but you never knew. This was the first study he had done and he wasn’t sure.

“We have a second site for the longer studies that you’ll be driven to, it isn’t far, after you’ve signed the contract for your participation.”

He nodded as he quickly filled out the form, wondering at some of the questions as he handed it back, but he didn’t get to say anything else before a man in a lab coat came out of the back carrying a clipboard with a bright grin. “Are you our participant?” Dean barely managed a nod before, “Excellent! I need you to sign this. It talks about the study, explains that the results from your participation will be used in our study but I can promise you that your name will not be linked to the data we use.”

Dean nodded along, half listening, as he took the pen and signed the necessary lines. Anything to get this moving and get to the money at the end.

“Great, Mr… _Winchester_ , if you’ll follow me we’ll head to the second site to start.” The man collected the form he’d filled out, added it to the clipboard and turned back to him to lead him towards the waiting vehicle.

He spaced out once they climbed into the vehicle and the man started chattering away, using far too many scientific terms and barely taking a breath, as Dean took in the scenery moving past the window.

“We’ve only recently started and haven’t had many participants so it’s great you showed up. This study is a bit… _different_ but the results will no doubt yield interesting results.”

Dean hummed an agreement as they rolled to a stop and he was led up the steps, through the lobby, down several halls and into a room.

“Take a seat. We’ve got a couple pills you’ll need to take and we’ll get started at once.”

The door opened almost the second the man stopped speaking and another person, this time a petite woman with curly hair, came in wearing an identical lab coat while carrying two cups.

“Do you need water to swallow?” she asked with a pleasant enough smile as Dean took the cup with several pills.

Dean barely bit back a comment at the opportunity her question gave him and instead reached out for the water, “That would be great, thanks.”

He tossed the pills into his mouth, took a quick drink and swallowed without thought. The woman left the room and the man in the lab coat leaned back in his chair, writing on a clipboard and humming to himself.

It was odd but he sat there silently waiting for the next step in this whole study process, figuring that something should be happening, as the minutes ticked by.

After several more minutes his head felt heavy, his thoughts sluggish and his body slumped in his chair. Dean opened his mouth to say something but nothing came out and his eyes drooped. Second by second things started to blur, his tenuous grasp on his focus started to fail and soon enough Dean was slipping into unconsciousness without a sound.

* * *

“Be careful with him.” The man breathed out as Dean Winchester was wheeled out of the first room and towards where the actual study would be taken place, “Put his belongings in a locker. He won’t need anything from there until the study is finished in three weeks.”

Jackson followed along behind as they moved deeper and deeper into the facility, into the elevator and down into the research lab designated for study 394.

It was a very taboo study, taboo enough that very few details were listed in their ad for participants but each detail was clearly written out on the contract.

Thankfully very few actually read the contract before signing otherwise they wouldn’t have results from ten different people, their eleventh getting ready to enter, and the additional injection each was administered helped to prevent much of anything for the patients to recall at the end of it.

Jackson could hear barking from the many different kennels as they wheeled past to the preparation room. One kennel was larger than the rest, a breeding stand specially created to hold human subjects and keep them stationary placed inside, with essentials each subject might need.

Next to it a station for recording research and monitoring the subject waited for them.

The three women who had signed up had a harder time in the conditions but each had given viable results. It had been important to see how the medications impacted women as well as men.

In the preparation room Dean was stripped until he was completely naked, each part of him was inspected and checked, before Jackson had him rolled over onto his belly.

A plump, round ass was offered up to their view and parting the cheeks revealed a dusty colored hole.

He selected a syringe from the tray laid out, used an alcohol swab to clean the area, before injecting Dean. Three injections followed before he reached for the bottle of lube.

With sure, steady fingers Jackson started to prep Dean’s tight, and per his information, virgin hole. Thanks to Dean’s unconsciousness there was little tension left in his body and the first finger sank in relatively easy.

Jackson finger fucked Dean a few times, pressing against his inner walls, as he started to loosen the muscles. One finger at a time, pumping in and scissoring, until Dean’s ass was taking four fingers.

“There we go.”

Most participants slept through three to four stimulations before the initial medications had worked into their system.

“He was chosen for Type C, correct?”

Dean was rolled back over, his limp dick placed in a metal cockcage and his balls with a metal band tight around the base, before sensors were carefully attached along his nude body.

“He’s in good health. Good age and condition. The results should be near perfect if he reacts similarly to previous participants. No doubt he’ll hate the canine aspect, who wouldn’t, but stimulation is stimulation.”

Jackson nodded absently, “I agree. I hoped he wouldn’t read over the contract before signing, there was such promise just from a glance.”

They hauled Dean up, moving him to the large kennel and draping him over the black breeding stand. He was laid belly down on the stand, his arms secured underneath the stand with thick straps and his legs, spread wide to keep him fully exposed and prevent much movement, were secured to the stand next.

“Are the cameras ready?”

“Yes.”

“Great. Start them the instant the first dog enters the kennel.”

Jackson moved out of the kennel, straightening to his full height with a sigh, before sitting down at the desk stationed right next to the participant’s kennel. He made sure all of his papers were laid out, his laptop in position and the remote ready.

The rest of the doses for their medications would be administered via syringe. “Ready?” a speaker on the desk had him reaching to press the answering button.

“Proceed with canine one.”

The first dog was a German Sheppard, hardly the biggest dog in the study, but it was a good starter and they always made sure to use the dogs in the exact same order. The smaller ones were used for the first few days and the rest of the study alternated between the largest and roughest breeds.

This one helped to start stimulating the body, particularly the anal region, as the beginnings of the medications worked into the system. Study 394 had multiple levels and it would, without a doubt, be well over a year worth of studies conducted before they had enough data.

It was a far more invasive test and medication filled study than most conducted for the males in Type B and C due to the alteration to their biology. The necessary stimulation was done using dogs and had the added bonus of saving them from various shelters.

Jackson had found that a far easier alternative than having humans fucking participants and there wasn’t worry about STDs. There was far too much red tape to use humans to repeatedly fuck participants and humans, unfortunately, didn't knot which helped in stimulating the participants anus.

He sat back and watched as the German Shepard, canine one, was released into the kennel where Dean lay unconscious on the breeding stand. Immediately the dog went to the prone form, mounting the naked body with little problem, before its legs locked around Dean’s waist and it started thrusting wildly.

Each dog was given their own medication to increase arousal and the scent from the lube helped to aid them in finding their goal: the human participant’s prepped and ready hole.

It took several thrusts before the dog finally caught and thrust inside, burying itself deep inside Dean’s slicked hole, before it started to roughly jerk its hips forward.

The fucking wasn’t as important to the study, though the participants’ biological reaction as the medications worked was important and the effect of the medications even more, but Jackson took notes.

Most reacted with horror, shock and shame upon realizing they were being fucked by a dog. Those emotions never changed despite the medications changing their bodies as each new dose was administered.

He recorded each session with a dog, marked it down to make sure to keep track of how many times the human body was stimulated before the medications started having noticeable effects, as the first of many knottings took place.

As expected Dean slept through the first four, each dog getting steadily bigger, before the fifth dog was allowed inside and started working its hips forward in an effort to find Dean’s very sloppy hole.

There was a groan and Jackson made a quick notation before standing up to move to the side of the kennel. It was time to calm the, no doubt, hysterical participant once Dean realized he was being mounted by a dog.

The straight male participants _always_ had the worst reactions.

* * *

Dean groaned lowly. His head felt fuzzy, his body ached and shifting didn’t allow him to move. Another groan escaped as the sensation of something rapidly pumping in and out of his ass slowly registered along with pleasure. There was a low ache that seemed dulled by the pleasure he could feel coursing through him.

He struggled to react, mind stumbling and tripping in its effort, as his eyes tried to open and another groan escaped. Warmth curled inside of him, twisting in his gut, as the feeling of pleasure dimly registered once more.

There was a weight on his back, heavy enough to catalog, and Dean realized the sensation was the feeling of a dick fucking his ass at a rapid pace. It was the only explanation and Dean tensed, at least he tried, but his muscles remained lax as he laid there draped over something.

“ _Wha_?”

“Mr. Winchester. Good. You’re finally awake! Usually most participants wake up during the third or fourth stimulation but you made it to your fifth. I was getting a little worried the medications might have had a stronger effect on you.”

“Where…where am I? What…who the fuck is— _ohhh_.” Arousal twisted inside of him and Dean bit back another moan as he tried to focus on the man next to him.

“Don’t worry. I’m here to answer all of your questions. You are at our second site in the basement lab for study 394 and we are well into the beginning. You’re already into the fifth stimulation and most changes start on the eighth so we should start seeing effects soon enough.”

“Stimulation? Wh—what the _fuck_?!” Dean tried jerking as something larger started to push against his aching hole and his mind struggled to understand the words the man in the lab coat was saying.

“That’s canine five’s knot.” The man answered. “It’s larger than the other four but your body will adjust as your muscles loosen. Once the study’s medications start to actively alter you the pain will greatly lessen and physically your body will start to adapt to the intrusion. You should start to naturally loosen instead of having to be manually loosened before penetration.”

Something large lodged inside of him and swelled, pressing against his insides and burning painfully, as Dean choked and tried to get away. He failed. “Get it out. Get it out.”

“That would cause far too much damage.”

Dean tugged at where his arms were strapped down underneath him and he tried to move his legs but he was strapped down and the dull ache at his hips from where his legs were spread far too wide. His drugged and addled mind couldn’t quite wrap around what was happening and it was causing panic.

“Knot? Canine? What the fuck kind of study is this?”

His mind was scrambling to ignore the fact that he had felt pleasure upon waking and that it was apparently due to a _dog fucking him_. The knot lodged inside of him, spreading him too far, had caused enough pain to diminish the pleasure from earlier but somewhere in his mind he was a bit turned on.

It was horrifying and Dean mentally lashed out at the thought.

“We use dogs to stimulate the anus instead of other humans, far too many additional precautions and steps, which helps the medications as they work to alter your system. Male participants receive an additional medication to aid in the biological changes to their body. Now we can’t tell you what we’re looking for but I can tell you the specifics of the study.”

“Now—” Dean whimpered as the knot inside of him tugged painfully at his hole as the dog moved and the large ball pulled from where it was locked inside. The dog stopped moving and as Dean tried twisting the knot rubbed against a spot inside him that had a spike of arousal lighting up inside.

“You will be given multiple doses of our medications through a syringe at set intervals, most of your time will be spent on the breeding stand with repeated stimulations and your vitals will be monitored. If you notice anything drastic, any sudden changes, you are to alert me immediately. We don’t want to harm you.”

The man continued, scientific babble Dean barely recognized from the vehicle, as the dog remained buried deep inside him.

It was humiliating and he flushed at the realization that he was naked, there were at least four cameras pointed at him that he could see and who knows who or what was behind him.

The study had said _nothing_ about getting fucked by dogs. The only time he’d ever heard of such a thing was when he accidently stumbled across some porn and it had been the most confusing fifteen minutes of his life.

His mind still felt rather fuzzy, not everything quite in working order, as the dog popped free and Dean felt something wet slipping from his loose hole. He could hear it hitting the ground and his cheeks heated further with embarrassment.

Dean couldn’t think of another time he had felt more exposed.

“Canine six.”

The two words had his head snapping to the right to regard the man standing there now holding a clipboard. He could hear movement behind him, the sound of footsteps, and another set of footsteps before a heavy weight was once more climbing on top of him.

Dean could feel the dog’s fur on his naked, flushed skin and feel its weight crushing him to the stand as claws scraped against his sides. It caused him to jerk and the feeling of the dog’s wet breath against his exposed nape caused him to freeze even as it kept fucking forward.

Its large dick pumped against him, missed his hole repeatedly, before Dean felt it catch. His breathing caught in his throat and within seconds the dog was slamming deep inside.

It burned.

This dog, based on the weight and the feeling of being stretched wider, let Dean know it was a far larger dog as it started to fuck him.

Hard.

Sound punched out of him, whimpers and groans and very reluctant moans, as the dog’s large dick pounded into him viciously. Sharp nails dug into his sides as it gripped him tightly and drool ended up on his naked back as it kept pounding into him from behind.

He was completely bound, unable to move, while he was fucked like an animals. Completely horrified Dean realized how that realization was turning him on to the point of a painful arousal.

Occasionally the dog’s dick would bump a spot inside him, a spot he started to wish it wouldn’t, as pleasure built in his gut and to Dean it felt _good._ He couldn’t hear the man in the lab coat talking or even the sound of him recording as the sensation of being fucked in a hard, single-minded way stole most of his attention.

“ _Fuck_.” The word punched out of him and Dean could feel his cheeks flushing with his growing arousal as several sharper jabs of the dog’s dick nailed that sweet spot inside of him. “ _Ohhh_. _Ohhh my goddddd_. _Fuck fuck fuck._ ”

It was humiliating and Dean desperately tried to hold back the sounds of pleasure as his body unwillingly responded to the dog fucking him and the situation, no matter how nightmare inducing, continued to cause arousal to build inside of him.

This was the first time, at least while he was _conscious_ , that he had _ever_ had anything in his ass and he was struggling with control to hold back how it was starting to feel so good.

A sound to the side had him turning and he could see disgust twisting the man’s features as he paused in recording to stare at Dean. “Maybe you _did_ know what this study was about and that’s why you showed up. Moaning like a whore for a dog fucking you. Disgusting.”

He wanted to protest but the dog started jerking its hips forward harder as its _fucking knot_ started to work past his sensitive, abused rim and lodged inside of him.

The round ball swelled up, far larger than the last one, as it locked them together and the dog started to empty its release inside of him. He groaned in pain, on that horrible edge of arousal, as it turned them ass to ass and caused the knot to painfully pull on his rim.

“That’s wrong.” The words were filled with disdain. “Actually _enjoying_ being fucked by an animal, used as a dog’s bitch, is _wrong_. It’s lucky that won’t impact the results of the study. We’ve never had this problem before.”

Dean blinked, pulled his mind away from surprising pleasure and the still slightly fuzzy feeling from the medications, as he looked at the researcher watching him.

“It isn’t necessary but if you’re going to enjoy it so much it would be best and we've used this for the more vocal protesters.” The man muttered as he walked away before Dean could say anything and the sound of the kennel opening behind him registered shortly after.

Fingers dug into his cheeks painfully causing him to open his mouth in protest before a large ball was shoved inside, pushed behind his teeth and stretched his mouth painfully wide, as straps on the sides dug into his cheeks as it was fastened behind his head.

_A ball-gag, what the fuck?_

Horror filled him as the researcher came around to look it over with a critical eye. “That should do. We’ll take it out for food and water but while you’re being stimulated it’s going to remain in. While the fact that you enjoy being a dog’s bitch doesn’t impact our study it would make everyone working on the study far more comfortable if we couldn’t hear how much you’re enjoying yourself. Honestly.”

Dean couldn’t talk.

Now he couldn’t even talk and there was a dog knotted in his ass, he was strapped down and medications he’d unknowingly agreed to take were working inside his body. And he _had moaned in pleasure at a dog fucking him._

“Now for your next series of injections.”

Footsteps caught his attention and Dean’s eyes darted around as he tried to see who it was but something was wiped on his skin before a sharp poke alerted him to the needle.

Whatever it was being injected burned and he whimpered into the gag as three more needles injected more of the study’s medications into him.

“Now this one is new. As the series of injections continues over the next three weeks the doses increase but are more spaced out. We’re hoping to eventually get the medication to a smaller number of injections but first we’re studying how the different medications interact as they target different parts of the human body.”

The last injection didn’t happen until the current dog’s knot shrunk enough to pop free leaving come to spill out of his gaping hole onto the floor.

“It’s always so messy but sometimes science is messy.” The man spoke as a hand braced against the base of Dean’s spine. This time the needle sunk directly into the area near his hole.

Dean’s whole body tensed as the medication was injected into him and it burned more than the last four. He couldn’t move away as it was pulled out and the man moved away from him.

“The pills were the initial stage, they helped to prepare your body for the injections and also helped sedate you until we got you ready.”

He didn’t fucking care. Dean could feel his mind turning slightly fuzzy as the medications worked through his body and occasionally something ached inside of him. With a muffled sigh he spaced out.

“Next canine.”

As his mind drifted and his body ached a new, larger dog mounted him and started to fuck against his ass while seeking out his overly sensitive hole. It huffed and growled lowly before its wide dick caught, thrust inside and it immediately started to piston harshly into him.

The feeling of being taken from behind, completely unable to do anything about it, was causing terribly inappropriate pleasure continue to fill Dean. His moans, though reluctant and without his control, were muffled by the large ball-gag and his ass clenched down at the sensation of the large dog fucking him.

“It could be the combination of medications.” A new voice spoke up from the side and Dean, through a haze of pleasure and the medications working in his system, took in the sight of a gorgeous little blonde watching him being used. “Each participant’s chemistry is different and it _could_ be causing him to react in such a manner. His pleasure centers could have been impacted.”

“Or he likes being fucked like a bitch in heat.”

“I think that’s it. Probably lied in his information. This can’t be the first time he’s had a dick in the ass.”

There were four of them in addition to the initial man watching him from outside of the kennel. Humiliation had him adverting his eyes as he laid there getting roughly fucked by a dog for everyone to see. Dean didn’t want to enjoy it, it was a fucking dog and it was buried in his ass, but he couldn’t help his reaction or how good it felt.

“I think he’s just a pervert but at least the results will hold.”

“A disgusting perverse human who _loves_ taking it in the ass by dogs.”

Their voices were a mixture of disgust and a bit of twisted amusement but Dean could still hear them over the rush in his ears and his fuzzy mind turned to focus on the simple sensation of being used.

* * *

By the end of the first week Dean’s body had spent most of the time on the breeding stand. He couldn’t keep track of how many times he’d been fucked and knotted, how many injections he’d received or the invasive tests to see the effect of the injections on his body.

Sometimes he came alert and wasn’t sure where he was.

He ate when he was given food, drank when given water and through a haze he relieved himself in the most humiliating manner in the kennel.

Occasionally they hosed him down to clean up the mess and keep it sanitary. He was sedated when the kennel was cleaned and when they did even more invasive tests on his body’s reactions.

By the sixth day Dean had started to look forward to the seemingly never-ending line of dogs that were used to keep his body constantly stimulated. The injections still burned, his hole was a ruined mess and his jaw ached from constantly being stuffed full of a large ball-gag.

The current dog buried deep in his ass, fucking him like its life depended on it, was a large mastiff. It _always_ burned when the dog thrust inside of him, all of the extra-large breeds did until his inner muscles had relaxed enough, but Dean moaned and desperately tried to move so he could get some kind of relief.

Being in a constant state of being on the edge of an orgasm was driving him insane and he begged breathlessly into the gag but no one would remove the cockcage from his violently aching dick.

Instead the researchers told him how wrong, how disgusting and vile, his responses for knowing he was being fucked by a dog. Even though it was part of their study none of the other participants had so thoroughly enjoyed being used like a wet hole for a dog.

They stopped calling him by his name, participant number or even simply participant. Instead they had taken to referring to him as ‘the bitch in heat’ whenever he was conscious.

“ _Ohhhhhh._ ” Dean’s eyes rolled in his head as he panted against the gag and his hole clenched desperately around the dick splitting him wide open. The dog’s thrusting picked up in the greedy kind of way they did when the dog was close to a knot and after violently rutting up against Dean’s plump ass the dog’s knot pushed past the ring of muscle.

It slipped inside Dean’s soaked hole, swelled to an impressive size and lodged there securely as the dog started pumping its release into him. Dean squirmed and whimpered, cheeks flushed and eyes wide with desperation, as the cockcage prevented his orgasm yet again.

“Far less resistance to a knot of considerable size. The inner muscles of his anus have started to loosen with simply arousal and stimulation instead of needing to be loosened with fingers. The exact response we wanted.”

Two researchers were discussing his latest results and Dean ignored them as one slipped in to give him another series of injections. The one near his hole wouldn’t occur until the dog was free.

They wouldn’t risk accidentally injecting the dog especially since that could potentially cause it to rip out of him and damage him far too much.

“And this one,” it was a redhead Dean would have gleefully picked up a week ago, taken back to his room and fucked through the night. The woman looked at his eyes, checked a monitor and the new machine attached to him. “Will alter some of your memory. It’s better for participants if the specifics of the study don’t stay in any of their memory banks.”

The needle broke the skin near his neck and Dean twitched, almost used to the injections, as his mind fuzzed and his eyes grew heavy.

“You’ll get the next one near your anus and a break while these medications settle.” She sounded more than satisfied as she waited out the current knot, making notes and tapping her foot while Dean struggled to keep his eyes open.

The desperate pleasure was still there, his body felt achy and his ass stuffed full even as his mind drifted.

He hated the way he responded to the stimulus, how much he had started to immediately harden at the feel of a furry weight pressing him down and that getting stuffed full of a knot would undoubtedly make him come untouched if that cage wasn’t preventing him.

Its knot popped free, an injection was administered and minutes later Dean was unconscious on the breeding stand once more.

* * *

The current participant was laid out on the examination table, sedated and strapped down, after he had been thoroughly cleaned. Four vials of blood sat on the counter along with several other samples as Jackson watched Eliza move forward with the speculum.

It took little stimulus for Dean’s anal muscles to relax in a very unnatural way, though exactly how one of the medications was meant to effect Dean’s body, as she inserted the speculum before slowly widening Dean’s hole.

Examination of the inner walls of Dean’s anus took well over ten minutes as changes due to the medications were cataloged. Next they checked for any damage and data was collected carefully along with the other results from previous examinations.

“He seems to be responding very well to the medications combined with the sexual stimulation. The participant starts to loosen and has started showing signs of self-lubrication when aroused.”

“His hormone levels have changed perfectly to show the medications have fully integrated with his body chemistry.”

“But his penis doesn’t harden when touched; it’s only through anal stimulation that he show true signs of pleasure, arousal or any other kind of reaction.”

Jackson pursed his lips. That last one was an unexpected side-effect of the medications they had been pumping into Dean Winchester since the beginning of the study.

“We’ll have to see if that remains a permanent alteration at the end of the study once the last dose has been administered to seal the series of injections or if he reverts back. It’s important to note.”

They removed the straps and Eliza carefully removed the speculum. Dean’s hole remained gaping, far wider than the dogs had fucked him open, as they moved his body from the table.

He was draped once more over the bench, strapped down and gagged.

“It’s rather disgusting that someone could actually enjoy knowing a dog was fucking them, right?” Jackson questioned as the final checks were made on Dean’s unconscious form, “I bet we wouldn’t have to strap him down at this point. He would probably lay there happily for the dogs to fuck for the rest of the study.”

“It is the first time one of the participants has responded like this.” Eliza frowned and shivered in disgust. “I had hoped we would get cleared for humans but dogs were far easier and we can have far more kept here for the study. Humans would make it harder to keep up the kind of stimulation we’ve been able to have with dogs and our study would get slowed drastically.”

Jackson nodded as he glanced at the claw marks on Dean’s sides, the puffy gaping hole nestled between the cheeks of a plump ass and the way Dean was simply draped there.

“He acts like a bitch in heat.”

“At least the dogs are enjoying themselves.” Eliza winked even though she couldn’t hide the revulsion of someone enjoying this part. Most of the participants were pleased to be unable to hold onto the memory of what the study entailed.

This one would probably mourn the loss of knowledge.

Or he might start getting hard when he saw a dog.

She stepped out as a new dog was brought in, mounted the participant like he really was a bitch in heat and started fucking forward in desperate, wild thrusts.

It was horrifying to watch but fascinating at the same time.

At least the dogs provided the necessary stimulation for the medications to start working though it was mostly the one medication injected directly into the area near the anus that mattered when it came to that aspect.

The rest were simply monitored through examinations, samples and data collected.

It was day sixteen.

Four dogs into the next round and Dean came awake, slowly, with a weak groan into his gag and a twitch of his muscles under freckled skin. The researchers watched as confusion filled glassy green eyes, freckled cheeks flushed with arousal at being fucked even while unconscious, and Eliza stepped into Dean’s view as the current dog rapidly pounded itself into Dean’s round ass.

“The sensation you’re experiencing is a dog currently using your anus.” She spoke in a clinical manner, “This stimulation has just begun but soon enough you’ll feel a large ball being pressed inside. It is just the dog’s knot. It is day sixteen of your three-week participation in our study.”

Dean weakly struggled against his restraints, eyes wide and unseeing, as the dog continued to fuck.

“It must be disorienting to constantly wake up and not remember what is happening or why.”

“It’s better. We can’t have the specifics of this study getting out and you know participants would still speak about it despite the confidentiality form they signed. At least we know from previous studies the memory impairment medication works brilliantly.”

* * *

Dean’s mind couldn’t hold onto thought. He couldn’t get past the sensation of a heavy weight pinning him down, the restriction of restraints, the ache of his jaw or the feeling of being fucked hard.

He was awash in sensation but unable to process it past the undeniable pleasure that built inside of him. It remained unable to flood through his body and offer some measure of relief.

“Even without the cockcage or the band around his balls he still won’t come.” Jackson murmured as he took in the view of Dean’s dark colored penis, hard and leaking, as it hung free while Dean was roughly fucked from behind.

“Add physical stimulation.” Came a female voice. Dean thought it might be familiar but he couldn’t place it.

The kennel door opened and Dean felt something wrap around his violently aching dick. It stroked up and down, alternating pressure, as he howled into his gag desperate for release but unable. The touch to his dick was torture.

“Keep stimulating him. The combination of anal and penis stimulation should cause release.”

It was agonizing. The touch of a hand on his dick and the sensation of a wide dick plowing through his soaked hole at the same time was maddening.

“Nothing. He’s hard as a rock but he isn’t coming.”

“That’s a new side-effect. Not good for him.” There was a hint of amusement in the tone at the last sentence.

Dean howled into his gag again, body tense and mind turbulent, as the hand moved away. He jerked and rocked against the breeding stand, hole fluttering around the dick now rutting up against his ass and the knot that sunk inside, easily slipping past the lack of resistance his hole had adapted to over three weeks before he was being flooded with dog come once more.

“We’ll have to see if that happens to any other subjects or if he’s an outlier. It will have to be disclosed either way.”

Footsteps moved closer and he heard the kennel open. “Last round of injections?”

“Yes. And this one needs to be administered after the sedative.”

Five injections were administered, the sixth only after the knot inside him slipped free with a gush of come and a seventh as Dean panted, limp and shaking, on the stand.

Darkness came up, swallowed him and dragged him under without a hint of resistance as Dean’s eyes slipped closed.

Slowly Dean blinked his eyes open, dazed and confused at his surroundings, as he shifted on the bed he was laid out on. His body ached all over, his mind felt fuzzy and his thoughts like they were struggling to move through molasses as he groaned.

“ _Fuck_.” He closed his eyes and shifted, trying to remember, before the sound of a door opening had him alerting to the fact that someone had joined him in the sparse room.

“Good afternoon, Mr. Winchester!” the man beamed at him, “I take it you had a good rest?”

“Rest?”

“Yes. The last dose really knocked you out. Are you feeling anything?”

“I ache.” Dean groaned, swallowed and tried to shake off the weird feeling of not remembering how he’d gotten to the room. “My head feels like I drank my weight in shots last night and I can’t remember a damn thing.”

The man furrowed his eyebrow and stepped close, a slightly apologetic look on his face, as he handed Dean a glass of water. “That seems to be a common side-effect to the medication. Unfortunately the memory loss only seems to happen every few or so people who participate.”

Dean had no way of knowing the man before him was lying and didn’t question the words.

“Hope you’re going to put that on the box.” He downed the rest of the water and squinted. “Why do I ache?”

“Ache?” again the man’s brow furrowed, “Sometimes there is muscle ache, though this is common in many medications on the market, but all of your results came back that you’re in sound health. It could be a full body ache but it should subside soon enough.”

That was a relief at least.

Dean struggled to remember, “How many more weeks left?”

“Oh you’re finished. All three weeks.”

“All three weeks? I can’t even remember one day of the study…” that was worrying and Dean shifted up, relieved his clothes were on, as he glanced around the room and focused on the man once more. “Is my memory of the last three weeks going to come back?

Because that was horrible. Dean wasn’t going to admit to Sam that he couldn’t remember the whole study and he could see the concern on the man’s face before him.

Of course he had to be the weird one who reacted poorly to a simply medical study.

“Depending on your brain chemistry it might not come back but don’t worry! We kept a very close watch on you and didn’t allow any harm to come to you. You stayed in the research facility the entire time, monitored and safe.”

He slowly nodded as he got to his feet and glanced around until he caught sight of his bag. “If I have any questions…?”

“You can get in contact. The information is in the folder on the desk, though as we explained we can’t get into results, but contact information if you have questions about your memory is enclosed. Just give your participant number.”

Dean signed a few more papers, promised not to discuss the study and left with a decent sized envelope of money. He wasn’t going to question receiving straight cash and instead shoved it into his bag, signed out at the original site and took the taxi the receptionist had called for him.

It had been far more than what he remembered the study saying in the ad.

* * *

Dean had picked up a woman that first night, _attempted_ to enjoy a night of fucking and instead had to tell her, completely embarrassed, that he just wasn’t as interested as he though.

The near constant need to have sex, arousal practically surging underneath his skin, had kept up since he had left the study. Dean couldn’t remember a time he had been this horny and women, even jerking himself off, did nothing. He couldn’t come or even get properly aroused.

Even if Sam was around he wouldn’t have mentioned his…embarrassing problem. His brother had left for the same study the day after. Sam had taken one look at the money, looked at how Dean was perfectly fine and had informed Dean he was going to participate. _I’m eighteen, Dean, and why not spend three weeks of the summer making a ton of cash? It’s a study…one you did and you’re perfectly fine!_

Now it was three days later and Dean still didn’t recall a single thing about the study but he hadn’t gotten a chance to tell Sam anything. At least he could see if Sam reacted similarly or if he needed to contact someone.

It was Dean’s third night at the same bar and the first actual signs of arousal had caught his notice. The man who had pressed up against him at the bar, dick hard in his jeans and pressed up against Dean’s ass as he grinded his hips forward suggestively, had arousal stirring inside of him. Dean couldn’t figure out _why_ the feeling of a man pressed up behind him, far larger than him, had arousal twisting inside of him.

And thirty minutes later found him in the man’s room, completely naked, handcuffed behind his back and bent over the edge of the bed as the man twisted fingers inside of his aching hole.

“What a little slut.” The older man chuckled darkly as his fingers twisted inside Dean and a choked whine escaped, “Slicked your little cunt up and got yourself ready to take dick, didn’t you? Knew what you wanted when you were in that bar.”

Dean couldn’t make heads or tails of what the guy was saying but the feeling of his hole getting fuller the more fingers added had his cheeks heating, his mouth fell open as he panted and he tried to shove back.

He couldn’t think of a time he was harder.

“I got what you need.”

Thick fingers dug into the flesh of his hip, the blunt head of a fat dick pushed easily past the ring of his rim, and then the man was slamming inside with a loud moan of approval as he buried every single inch of his monster dick into Dean’s once empty hole.

“Fuck. You feel perfect around me.”

Fingers dug even harsher into his hips as the man started to viciously pound into his ass. The loud slap of skin against skin filled the room along with the noisy creak of the bed protesting the strength behind the trusts and Dean’s loud, begging moans spilled out into the air.

He couldn’t stop the response, how _good_ it felt to have a dick buried balls deep in his ass and how he needed _more_. The horrible need for sex was at least marginally helped by having his ass fucked full.

Dean panted and cried out, near sobbing with need to get off, as the man greedily fucked his ass. There was a loud bang against the wall, someone telling them to shut up, but Dean didn’t care as he tried to rut against the mattress in an effort to get some relief.

The man didn’t seem to notice, wasn’t touching him, but instead roughly plowed him from behind as the sounds of the protesting mattress became noisier along with the man’s loud, filthy words about how good Dean felt around his dick.

“Gonna fuck this ass of yours all night. Not gonna let you come until you come on my dick like a good slut.”

Tears of frustrated arousal spilled down his cheeks and Dean grunted, shoved back and wished for relief.

He couldn’t understand why it wasn’t coming. The edge of release was right there, the man kept hitting that spot inside of him, and Dean couldn’t come. He begged and pleaded for the man to touch him but it only earned throaty chuckles.

Soon enough a groan followed, the man’s hips jerked forward several times and wetness slipped from Dean’s loose hole as a softening dick slipped free with another groan.

“Hell of a fuck. You ain’t a prostitute, are you?”

Dean huffed out a _no_ , confused at his own response and humiliated at being completely dominated by an unknown older man, as the man laughed roughly.

“You should be. This plump ass of yours could make you a fortune.”

He jerked when a hand smacked his ass, the sting causing his breathing to hitch and arousal to spike, before the man gripped him. Dean found himself manhandled into the center of the bed, belly down and naked ass exposed.

“Give me a bit. I think I have a pill around here and I can really spend the night fucking you right to orgasm. I know sluts love it when they come untouched from a good fucking.”

But hours and hours, with the aid of medication and toys, Dean remained on the edge and his poor neglected dick ached horribly. It was dark, hard and leaking but nothing could bring him to come even as his body effortlessly responded to stimulation to his gaping hole.

He had sobbed, howled, begged and pleaded but he hadn’t come.

Next to him the man snored, fucked out and with a blissful smile on his face, as Dean tried jerking himself off as he sat on the edge of the bed. No matter how he touched himself, what he thought about, it only got worse.

Even fingering his sloppy ass did nothing for the relief and only seemed to cause his hole to get even wetter.

Dean stepped into the bathroom, cleaned himself up and almost sobbed tucking his painfully hard dick into his pants as he slipped out of the room. The next two weeks of fucking through twenty-six men, several times he even managed to have two buried in his hole at once, produced no help for his problem. It was luck that Sam was away at that study instead of there to see Dean almost constantly bringing men back to the room for sex or disappearing to seek it elsewhere.

Females didn’t do it for him anymore.

Any kind of stimulation to his ass resulted in actual arousal, slick and his hole naturally loosening.

IT appeared that no amount of fucking, touching, teasing, sucking or anything else sexual could bring him release. Dean found himself unable to orgasm but desperate to bend over and take it in the ass daily.

It was an almost desperate, insatiable need to be fucked that he couldn’t deny. There was no way he was calling those people at the study or saying a damn thing to Sammy. He couldn’t stand the humiliation

He wasn’t going to touch the reason why the sight of a dog earlier that day had caused his dick to harden painfully with a fifty-foot pole.

 

**Author's Note:**

> In case anyone was curious I created a tumblr account at [thursdayhunter](http://www.thursdayhunter.tumblr.com) for communication outside of the AMAZING comments you all leave for me on my fics. It's one way I've received prompts or at least ideas for some of my fics on here. I do consider prompts sent to me or if someone has found a prompt on the kink-meme they think might be up my alley.
> 
> As always I hope someone enjoyed the latest fic (I thought a few of you might like it). It wasn't as dark as most though it wasn't light by any means but I'm sure at least a few of you liked this one. What did you think? Messed up? Kinky? Thought provoking? Just what you were secretly looking for?
> 
> Written for a prompt that wanted the following:
> 
> -Dean/Dogs  
> -Dubcon  
> -Knotting  
> -Medical kink  
> -Dean going to nearby research facility for study offering good money  
> -Dean signs contract without reading specifics  
> -Dean takes pills offered and wakes up getting fucked by a dog  
> -Dean is both horrified and turned on  
> -Researchers are disgusted by Dean enjoying it and humiliate/insult him  
> -There are long lasting side effects to Dean's sexuality/body/mind  
> -Add kinks as you please


End file.
